Intravascular diseases are commonly treated by relatively non-invasive techniques such as percutaneous translumenal coronary angioplasty (PTCA). PTCA is well known in the art and typically involves the use of a guide catheter, a guide wire and a balloon catheter, possibly in combination with other intravascular devices. A typical balloon catheter has an elongate shaft with a balloon attached proximate its distal end and an inflation manifold attached proximate the proximal end. In use, the balloon catheter is advanced through a lumen in the guide catheter over the guide wire such that the balloon is positioned adjacent a restriction in a diseased vessel. The balloon is then inflated and the restriction in the vessel is opened.
PTCA devices come is a variety of shapes and sizes depending on the nature of the anatomy in which the device will be used. For example, a PTCA procedure may be performed in either the right or left coronary arteries, each requiring a guide catheter having a different shape on the distal end to track the vessel anatomy. In addition, a PTCA procedure may be performed in either (or both) a proximal or distal portion of each of the coronary arteries, each requiring a different sized balloon catheter. Furthermore, there are anatomical differences between patients which may require a different shaped or sized intravascular device for treatment.
To meet the above cited needs, guide catheters and balloon catheters are manufactured in various sizes and shapes as a total unit which is used once and discarded. However, often only a portion of each device is of different size or shape. For example, only the distal portion of a guide catheter varies in shape depending on the given anatomical geometry to be navigated while the proximal portion of the guide catheter is of the same size and is almost always a straight tubular member. Accordingly, it would be desirable to have a guide catheter with a standard proximal portion and an interchangeable distal portion. Likewise, it would be desirable to have other intravascular devices with interchangeable parts so that the portion of the device which does not have to change size or shape can be used with multiple interchangeable portions. By using a standard portion in conjunction with multiple interchangeable portions, hospital inventories can be reduced, manufacturing costs can be reduced, and unnecessary waste can be eliminated.
With present intravascular devices, when it becomes necessary to change to a device having a different size or shape in the distal portion, it is necessary to remove the entire device from the vascular system of the patient and replace such device with the new device. In general, this requires pulling the entire device back through the vasculature, out the point of insertion at such location as the femoral artery, and reinserting an entirely new device by threading such device over the guide wire up to the treatment site. This increases the overall treatment time when it is necessary to use devices of different size or shape in the procedure. Therefore, it would be desirable to have an intravascular device with a single proximal portion which is standardized to be utilized with multiple interchangeable distal portions which can be changed to the desired distal portion during an intravascular procedure without removing the standardized proximal portion from the patient.